Press for vulcanizing-molds.



c. H. GRAY.

PRESS FOR VULCANIZING MOLDS.

APPLICATION FILED Nov. i, 191e.

' 1,234,330. Patented July 24, 1917.

-residingfin Essex, England,

sure on the Vmolds as :STATES rATENToFmoa CHRISTIAN ymuxlrrri'roi'r enAYQ'jor Essmmrenn'in.

To all whom it may concern:

Be it known that 1 GHRISTIAN-HAMHAON GRAY, i a subject of Vthe Kin of- England,

certain ynew and. useful Improvements'. 'in

following 1s a specification.'

This invention isfor. improvenie nitsy in for' relating -to presses` for `vu1caniz1ng-`molds, and has 4for its object to' provide a press which cannot he operated to put such pres-` or itself.

the bed upon guiding members constructed' to engage with the plate ltoexert van upward thrust thereon but to be movable downward relatively to the .plat-e without exert-v ing 'a Vdownward thrust thereon and powerdrlven mechanism to 'raise the plate by descend under the-action of means of thesaid members and permit it 'to It has before been propose to raise and lower a top-plate of a vulcanizing-mold by means which cannot exert downwardpressure upon it,'but in use this plate was in- 'tended to be locked in position prior to applying pressure by a specially constructed ram,

It has also been proposed to force'down the ram of an electrical press' by' a lever having one end'ccnnccted to a nut engaged by a springbontrolled screwfthreadedspindle, so that the ram would be positively lowered and forced 'down by the. operation vof the screw-threaded spindle until the pressure of the con-trolling spring was overcome, 'when the spindle would advance against the spring, thenut and ram meanwhile remainlng stationary, and in its vmovement operf ate aswitch to cut ofthe driving current.

' It will be seen' that neither of'these pro# posais anticipates the employment of thedead Weight` of'a press-plate to ,apply thereiuired pressure., 4

A'n the accompanying 'drawings which illustrate one method of "carrying out' this invention- Figure l isa vertical section throughthe 4 press showing a few 'molds in position;

Fig. 2 is4 a plan of an end-Portion Aofthe press, and u 4 4raass ron vULcANIzI'nG-nonns.

Specication of Letters Patent.

ave :invented l whose-interior is screw-threa ed tocn'gae to either damage them Y."

tongue Af on the left-hand, ltop plate of thepress,

ter-'gearing Vby which they' are connected.,

lA"""strikes thestop F- andraises the'v rod raised, and thusthe sivvitch-'army E of 'r'atentea Julyfac 191'?.

"Applicationnleanovembr'r,191e,` serialrrafiaasca.

Fig. 3 is a' horizontal section .througha 55.` portlon of one ofthe plates ofthe, press.

j The 'same letters. indicate the same'parts ughout thedrawings 'fl .5 he bottom plate A of the press is a .fix- Presses for "Vulcanizing-Molds, ofiwhichthe. E

ture being carried 'on supports A1,v Theeozuppe'r. plate A2- 'hasguidellugs Asfsecured :one'fat' eachiend Each of. theselu s basa' square hole which takes avnut Bv w 4ose ex' terior, is square to fit the lu loosely? gend"4 'A 65 eadof a verticalv lifting-spindle, bottom' of each nutfi's flangedjatgBV to' a ertheunder-face of the lug'Af, 'The Ii lesBl. are geared b. miter'jgearing-toj'- driving-.shaft C `Whic receives motion van electric 'motor -D through pulleys tothelever E at El sfa PF: which slidesin bearings .indica d ,inilottede lines at F2.' F ixed'to' the. rod stopslFf?, j'

F* respectively whichcoperate avi-thy `a ion-of .appli as4 fol# l' i l The operat lows:- v -V To raise'the top 'platelet-the press, the lever E 'is ulled down sothat, theswitchf 18'5 arm Ea Wil be thrown 'evento u p` position indicated on the motorsfD, and with this movement of the lev er 1 ],.the'i'verticali` the lug A* of the lessplate A2, 'The'vm switch-arm E2, o erates the shaft; d

thus drives the splndles-Bthro'llgh'r `e the Vsaid shaft, and in `this manner the niits As they' advance, they pick'up theplatejA 4A2 -vby means ofthe flanges B2 which'l'iey V under' the lugs A and raise the'plate free ofthe' molds inthe' press, .which molds'. are f# indicated at" G. As soon as the plate' isf free of the molds, `the tongue A* Aon the flug F, so that' bjthismeans the lever E-. is

maar is taught: over o e@ feta?" im A2 is had in the as` been raised. 4 l

To return the plate A2 the lever E is position to which it raised and thus the switch-arm E3 is brought over tothe down position 011 the motor D. .This reverses the motor so that the operation of the parts is reversed andtheplate A2 is lowered until it rests on the molds G. By

"this time the tongue A4 has come into contact 'with the stop F3 and has thus moved the switel'i-ar1n E3 of the motor D over to the stop position. The motor does not lin` mediately stop so that the nuts B still continue to travel down sliehtly, but this has no effect upon the plate A? as the nuts B tree in the lugs .A3 and thus the plate A2 only lies on the molds With its own weight.

lt will thus be seen that in no circumstances can greater pressure be put upon the vlate A2 than is due to its own Weight, and

' and bottom. walls of each hollow plate. The upper plate may be lagged, as indicated at Al, and the lagging may extend down in the form of a hood over the sides of the bottom plate, as indicated at All, though at the ends Where this downward. extension is sho'wn, a slot is necessarily provided in th'e lagging for the lugs A3.

Should the automatic .mechanism for stopping the motor become deranged at any time, noharm. Will accrue to the press, as the spindles B1 are provided with plain' eX- tensions B1* which would receive the nuts B so that the plate would not be thrown from the spindles but would merely rest at the top of the same while the spindles continued to rotate.

Obviously other means may be employed for raising and lowering the plate Afec-v cording' to this invention, for example, instead of the nuts B, the plate could be low ered by chains or other flexible means which cannot exert any downward thrust upon the plate, so that 'when brought down upon the molds, a thrust equal. to its own Weight only, would be exerted upon the latter, Further, where it is preferred to maire the plate itself lighter than will give the required pressure, weights may be placed upon it to the re quired amount, the object being never to allow the pressure to exceed the preltjletermined n'iaximum value.

That l claim as my invention and desire to secure by Letters Patent is l. In a press for 'vulcanizing molds,- the combination of a bed, a prf-:ss-plate supported above the bed upon. guide members constructed to engage the plate to exert an upward thrust thereon but to 'be movable downward relatively to the plate Without ex-v erting a dov-'nward thrust thereon, and

power-driven meehanism'to raise the plate by means of said members and permit it to descend under the action of gravity alone, i

substantially as described.

In a press for vulcanizing-molds, the combination o a hed, a press-plate Vsupported above the bed upon guidefmembers constructed to engage witlrthe plate to eX- ert an upward thrust thereon but to be Inovable downward relatively to the platewithout exerting a downward thrust thereon, and power driven mechanism provided With automatic stop-gear controlled by the posi- Ation of said plate relatively to the bed' to raise the plate by means of the said members and permit it to descend under the action of gravity alone, substantially as set tort-h.

In testimony vwhereof I have signed my name to this specification.

CHRISTIAN' HAMILTUN GRAY. 

